Impact Event at the Permian-Triassic Boundary: Evidence from Extraterrestrial Noble Gases in Fullerenes
It has been twenty years since Luis Alvarez suggested that the dinosaurs were extinguished by a meteor impact that killed much of the life on earth. His evidence was in a thin layer of iridium-rich soil that corresponded with the extinction, and the fact that iridium is much more abundant in some meteors than it is on earth.